Respirator that has inward nose region fold with high level conformation

Abstract

A flat fold filtering face piece respirator 10 that includes a mask body 12 and a harness 14 . The mask body 12 includes a filtering structure 16 that contains a cover web 48, 50 and a filtration layer 52 that contains electrically-charged microfibers. The filtering structure 16 is folded over upon itself in a nose region 32 of the mask body 12 to be at least 1 centimeter or more wide and to extend across the upper perimeter of the mask body in a generally straight line when the respirator is in the folded condition. The filtering structure 16 has a deflection greater than about 0.5 millimeters and has a recoverability of at least 40% in the folded condition. A mask body having this construction is beneficial in that it does not need to use a nose foam to obtain a snug fit over the nose.

1 - 15 . (canceled) 
     
     
         16 . A flat fold filtering face piece respirator that comprises:
 a harness; and   a mask body that lacks a nose foam and that comprises a filtering structure that contains a cover web, and a filtration layer that contains electrically-charged microfibers, the filtering structure being folded over upon itself in a nose region of the mask body to create an overlapped portion having a width (W) that is 1 centimeter or more wide and that extends across the upper perimeter of the mask body in a generally straight line when the respirator is in a folded condition, the folded filtering structure having a deflection greater than 0.8 mm and having a recoverability of at least 50% when tested under the Deflection and Recoverability Test, wherein the folded filtering structure has a thickness (T) of at least 3 mm.   
     
     
         17 . The respirator of  claim 16 , wherein the filtration layer is located between the first and second cover webs. 
     
     
         18 . The respirator of  claim 16 , wherein the folded filtering structure has a thickness (T) of no greater than 5 mm. 
     
     
         19 . The respirator of  claim 16 , wherein the fold has a width (W) of 1 to 3 cm. 
     
     
         20 . The respirator of  claim 19 , wherein the fold has a width (W) of 1.2 to 2 cm. 
     
     
         21 . The respirator of  claim 16 , wherein the fold extends in a generally straight line for 10 to 35 cm. 
     
     
         22 . The respirator of  claim 21 , wherein the folded over portion of the mask body provides a peripheral edge that extends in a generally straight line parallel to a second internal edge. 
     
     
         23 . The respirator of  claim 16 , wherein the fold extends in a generally straight line for 15 to 30 cm. 
     
     
         24 . The respirator of  claim 16 , wherein the fold in cross section is U-shaped. 
     
     
         25 . The respirator of  claim 16 , wherein the fold in cross section is S-shaped. 
     
     
         26 . The respirator of  claim 16 , wherein the fold in cross section is W-shaped. 
     
     
         27 . The respirator of  claim 16 , wherein the mask body comprises a nose clip in the nose region. 
     
     
         28 . The respirator of  claim 16 , wherein the deflection is greater than 0.9 and the percent recovery is at least 55%. 
     
     
         29 . The respirator of  claim 16 , wherein the filtration layer is located between the first and second cover webs. 
     
     
         30 . The respirator of  claim 29 , wherein the nose clip is located beneath the second cover web.